1 * Major changes in Autoconf 2.61b (????-??-??)
3 ** AC_C_BIGENDIAN now supports universal binaries a la Mac OS X.
5 ** Autoconf now requires GNU M4 1.4.5 or later. Earlier versions of M4 have
6 a bug in macro tracing that interferes with the interaction between
7 Autoconf and Automake. GNU M4 1.4.8 or later is recommended.
9 ** Warnings are now generated by default when an installer invokes
10 'configure' with an unknown --enable-* or --with-* option.
11 These warnings can be disabled with the new AC_DISABLE_OPTION_CHECKING
12 macro, or by invoking 'configure' with --disable-option-checking.
14 ** For portability with the eventual M4 2.0, macros should no longer use
15 anything larger than $9 to refer to arguments.
17 * Major changes in Autoconf 2.61a (2006-12-11)
19 ** AC_FUNC_FSEEKO was broken in 2.61; it didn't make fseeko and ftello visible
20 on many platforms. This has been fixed.
22 ** AC_FUNC_SETVBUF_REVERSED is now obsolete. It is still defined for backward
23 compatibility but it does nothing. The macro was already
24 obsolescent, as the last systems to have the problem were those
25 based on SVR2, which became obsolete in 1987. The macro had bugs
26 on some modern systems and could no longer be maintained reliably
27 due to lack of ancient systems to test it on.
29 ** config.status now uses awk instead of sed for most substitutions, for speed.
31 - As a side effect multi-line values of substituted variables no
32 longer have a small limit in total size, though for portability
33 each line should not exceed the POSIX length limit for text lines.
35 - It is now documented that Makefile.in should not contain
36 overlapping variable occurrences, e.g., @VAR1@VAR2@.
37 Autoconf's behavior was always iffy in such cases, and the
38 awk implementation has changed the behavior.
40 ** Many uses of 'echo' have been rewritten so that Autoconf-generated
41 scripts have fewer problems with strings or file names containing
42 embedded special characters such as backslash or leading "-". This
43 was implemented by using `printf '%s\n' "$foo"' instead of `echo
44 "$foo"' when printf works. Due to the implementation technique
45 used, Autoconf-generated scripts now run considerably more slowly
46 on ancient implementations lacking printf. However, this should
47 not be a problem, since Autoconf-generated scripts in practice
48 invariably find a more-modern shell these days.
50 * Major changes in Autoconf 2.61 (2006-11-17)
52 ** New macros AC_C_FLEXIBLE_ARRAY_MEMBER, AC_C_VARARRAYS.
54 ** AC_ARG_ENABLE and AC_ARG_WITH now allow '.' in feature and package names.
56 * Major changes in Autoconf 2.60b (2006-10-22)
59 Autoconf-generated shell scripts no longer export BIN_SH, due to
60 configuration hassles with this. Installers who need BIN_SH in
61 their environment should set it before invoking 'configure' and
62 'make'. As far as we know, this affects only Unixware installations.
65 The documentation now says that the following macros are obsolescent,
66 as they are superseded by Gnulib:
68 AC_FUNC_FNMATCH AC_FUNC_FNMATCH_GNU AC_FUNC_GETLOADVG AC_REPLACE_FNMATCH
70 New programs should use the Gnulib counterparts of these macros.
71 We have no current plans to remove them from Autoconf.
73 ** AC_COMPUTE_INT no longer caches or reports results.
75 ** AC_CHECK_DECL now also works with aggregate objects.
77 ** AC_USE_SYSTEM_EXTENSIONS now defines _TANDEM_SOURCE for NonStop platforms.
79 ** GNU M4 1.4.7 or later is now recommended.
82 New M4sugar macro, which is more secure than the POSIX M4 maketemp.
85 Now an alias for m4_mkstemp.
87 * Major changes in Autoconf 2.60a (2006-08-25)
89 ** GNU M4 1.4.6 or later is now recommended.
91 ** The check for C99 now tests for varargs macros, as documented.
92 It also tests that the preprocessor supports 64-bit integers.
94 ** Autoconf now uses constructs like "#ifdef HAVE_STDLIB_H" rather than
95 "#if HAVE_STDLIB_H", so that it now works with "gcc -Wundef -Werror".
97 ** The functionality of the undocumented _AC_COMPUTE_INT is now provided
98 by a public and documented macro, AC_COMPUTE_INT. The parameters to the
99 two macros are different, so autoupdate will not change the old private name
100 to the new one. _AC_COMPUTE_INT may be removed in a future release.
102 ** AC_TYPE_LONG_LONG_INT and AC_TYPE_UNSIGNED_LONG_LONG_INT now require
103 that long long types be at least 64 bits wide, as C99 and tradition
104 requires. Formerly, they accepted implementations of any width.
107 * Major changes in Autoconf 2.60
109 Released 2006-06-23, by Ralf Wildenhues.
111 ** Autoconf no longer depends on whether m4wrap is FIFO (as Posix requires)
112 or LIFO (as in GNU M4 1.4.x). GNU M4 2.0 is expected to conform to Posix
113 here, so m4wrap/m4_wrap users should no longer depend on LIFO behavior.
115 ** Provide a way to turn off warnings about the changed directory variables.
117 * Major changes in Autoconf 2.59d
119 Released 2006-06-05, by Ralf Wildenhues.
121 ** GNU make now recommended for VPATH builds
122 INSTALL now suggests VPATH builds (e.g., "sh ../srcdir/configure")
123 only if you use GNU make. In practice, other 'make' implementations
124 have too many subtle incompatibilities in their support for VPATH.
125 Many packages (including Autoconf itself) are portable to other
126 'make' implementations, but some packages are not, and recommending
127 GNU make keeps the installation instructions simpler.
129 ** Even more safety checks for the new Directory variables:
130 Warn about suspicious `${datarootdir}' found in config files output.
132 ** AC_TRY_COMMAND, AC_TRY_EVAL, ac_config_guess, ac_config_sub, ac_configure
133 These never-documented macros and variables have been marked with
134 comments saying that they may be removed in a future release,
135 because their use can lead to unintended code being executed.
136 If you need functionality that only these macros or variables
137 currently supply, please write bug-autoconf@gnu.org.
139 ** AC_SUBST, AC_DEFINE
140 Literal arguments to these are passed to m4_pattern_allow now.
143 Passing 'ac_cv_prog_cc_stdc=no' to 'configure' now sets ac_cv_prog_cc_c99
144 and ac_cv_prog_cc_c89 to 'no' as well, for backward compatibility with
145 obsolete K&R tests in the Automake test suite.
154 Now more robust with special characters in file names, or when
155 multiple processes create the same directory at the same time.
157 ** Obsolescent macros
158 The documentation now says that the following macros are obsolescent:
159 they test for problems that are so old that they are no longer of
160 practical importance on current systems.
162 AC_C_BACKSLASH_A AC_FUNC_MEMCMP AC_HEADER_DIRENT
163 AC_C_CONST AC_FUNC_SELECT_ARGTYPES AC_HEADER_STAT
164 AC_C_PROTOTYPES AC_FUNC_SETPGRP AC_HEADER_STDC
165 AC_C_STRINGIZE AC_FUNC_SETVBUF_REVERSED AC_HEADER_SYS_WAIT
166 AC_C_VOLATILE AC_FUNC_STAT AC_HEADER_TIME
167 AC_FUNC_CLOSEDIR_VOID AC_FUNC_STRFTIME AC_ISC_POSIX
168 AC_FUNC_GETPGRP AC_FUNC_UTIME_NULL AC_PROG_GCC_TRADITIONAL
169 AC_FUNC_LSTAT AC_FUNC_VPRINTF AC_STRUCT_TM
171 New programs need not use these macros. We have no current plans to
175 For compatibility with future Libtool 2.0, autoreconf will invoke
176 libtoolize with the option `--ltdl' now, if LT_CONFIG_LTDL_DIR is
179 * Major changes in Autoconf 2.59c
181 Released 2006-04-12, by Ralf Wildenhues.
183 ** The configure command now redirects standard input from /dev/null,
184 to help avoid problems with subsidiary commands that might mistakenly
185 read standard input. AS_ORIGINAL_STDIN_FD points to the original
186 standard input before this redirection, if you really want configure to
187 read from standard input.
189 ** Directory variables adjusted to recent changes in the GNU Coding Standards.
190 The following directory variables are new:
192 datarootdir read-only architecture-independent data root [PREFIX/share]
193 localedir locale-specific message catalogs [DATAROOTDIR/locale]
194 docdir documentation root [DATAROOTDIR/doc/PACKAGE]
195 htmldir html documentation [DOCDIR]
196 dvidir dvi documentation [DOCDIR]
197 pdfdir pdf documentation [DOCDIR]
198 psdir ps documentation [DOCDIR]
200 The following variables have new default values:
202 datadir read-only architecture-independent data [DATAROOTDIR]
203 infodir info documentation [DATAROOTDIR/info]
204 mandir man documentation [DATAROOTDIR/man]
206 This means that if you use any of `@datadir@', `@infodir@', or
207 `@mandir@' in a file, you will have to ensure `${datarootdir}' is
208 defined in this file. As a temporary measure, if any of those are
209 found but no mention of `datarootdir', the substitutions will be
210 replaced with values that do not contain `${datarootdir}', and a
211 warning will be issued.
213 ** @top_builddir@ is now a dir name: it is always nonempty and doesn't have
214 a trailing slash. Similar change will be made to ac_top_builddir in a
215 future release; the old style value, which matches (../)*, is (and will
216 continue to be) available as ac_top_build_prefix.
219 New macro to check for support of 'typeof' syntax a la GNU C.
221 ** AC_CHECK_DECLS_ONCE, AC_CHECK_FUNCS_ONCE, AC_CHECK_HEADERS_ONCE
222 New "once-only" variants of commonly-used macros, to make 'configure'
223 smaller and faster in common cases.
226 New macro to check for strtold with C99 semantics.
229 New macro that lets builder disable assertions at 'configure'-time.
232 Now checks for X11/Xlib.h and XrmInitialize (X proper) rather than
233 X11/Intrinsic.h and XtMalloc (Xt).
235 ** AC_PRESERVE_HELP_ORDER
236 New macro that causes `configure' to display help strings for AC_ARG_ENABLE
237 and AC_ARG_WITH arguments in one region, in the order defined. The default
238 behavior is to group options of each classes separately.
240 ** AC_PROG_CC, AC_PROG_CXX
241 No longer automatically arrange to declare the 'exit' function of C,
242 when a C++ compiler is used. Standard Autoconf macros no longer use
243 'exit', so this is no longer an issue for them. If you use C++, and
244 want to call 'exit', you'll have to arrange for its declaration
245 yourself. But we now suggest you return from 'main' instead.
247 ** AC_PROG_CC_C89, AC_PROG_CC_C99
248 New macros for ISO C99 support. AC_PROG_CC_C89 and AC_PROG_CC_C99
249 check for ANSI C89 and ISO C99 support respectively.
252 Has been unobsoleted, and will check if the compiler supports ISO
253 C99, falling back to ANSI C89 if not. ac_cv_prog_cc_stdc is
254 retained for backwards compatibility, assuming the value of
255 ac_cv_prog_cc_c99 or ac_cv_prog_cc_c89 (whichever is valid, in
258 ** AC_STRUCT_DIRENT_D_INO, AC_STRUCT_DIRENT_D_TYPE
259 New macros for checking commonly-used members of struct dirent.
262 The substituted value can now contain newlines.
265 The substitution now occurs only when @variable@ is on a line by itself,
266 optionally surrounded by spaces and tabs. The whole line is replaced.
268 ** AC_TYPE_LONG_DOUBLE, AC_TYPE_LONG_DOUBLE_WIDER
269 New macros to check for long double, and whether it is wider than double.
270 The old macro AC_C_TYPE_LONG_DOUBLE has been marked as obsolete;
271 applications should switch to the new macro.
273 ** AC_TYPE_INT8_T, AC_TYPE_INT16_T, AC_TYPE_INT32_T, AC_TYPE_INT64_T,
274 AC_TYPE_INTMAX_T, AC_TYPE_INTPTR_T, AC_TYPE_LONG_LONG_INT, AC_TYPE_SSIZE_T,
275 AC_TYPE_UINT8_T, AC_TYPE_UINT16_T, AC_TYPE_UINT32_T, AC_TYPE_UINT64_T,
276 AC_TYPE_UINTMAX_T, AC_TYPE_UINTPTR_T, AC_TYPE_UNSIGNED_LONG_LONG_INT
277 New macros to check for C99 and POSIX types.
279 ** AC_USE_SYSTEM_EXTENSIONS
280 New macro to enable extensions to Posix.
283 New macro which is defined to the name of the first declared config header
284 or undefined if no config headers have been declared yet.
287 The macro correctly handles quadrigraphs now.
289 ** AS_BOURNE_COMPATIBLE, AS_SHELL_SANITIZE, AS_CASE
290 These macros are new or published now.
293 New macro for copyright notices in testsuite files.
295 ** ALLOCA, LIBOBJS, LTLIBOBJS
296 Object names added to these variables are now prefixed with `${LIBOBJDIR}',
297 as in `${LIBOBJDIR}alloca.o'. LIBOBJDIR is meant to be defined from
298 `Makefile.in' in case the object files lie in a different directory.
299 The LIBOBJDIR feature is experimental.
302 Supports --no-recursive now.
304 ** New macros to support Erlang/OTP.
305 New macros for configuring paths to Erlang tools and libraries:
306 AC_ERLANG_PATH_ERLC, AC_ERLANG_NEED_ERLC, AC_ERLANG_PATH_ERL,
307 AC_ERLANG_NEED_ERL, AC_ERLANG_CHECK_LIB, AC_ERLANG_SUBST_ROOT_DIR,
308 AC_ERLANG_SUBST_LIB_DIR.
310 New macros for configuring installation of Erlang libraries:
311 AC_ERLANG_SUBST_INSTALL_LIB_DIR, AC_ERLANG_SUBST_INSTALL_LIB_SUBDIR.
313 ** The manual now mentions Gnulib more prominently.
315 ** New macros to support Objective C.
316 AC_PROG_OBJC, AC_PROG_OBJCPP.
318 * Major changes in Autoconf 2.59b
320 Released 2004-08-20, by Paul Eggert.
323 New macro that computes the default alignment of a type.
325 ** AC_CHECK_TOOL, AC_PATH_TOOL, AC_CHECK_TOOLS
326 When cross-compiling, these macros will give a warning if the tool
327 is not prefixed. In the future, unprefixed cross tools will not
328 be detected; please consult the info documentation for information
329 about the reason of this change.
331 ** AC_CHECK_TARGET_TOOL, AC_PATH_TARGET_TOOL, AC_CHECK_TARGET_TOOLS
332 New macros that detect programs whose name is prefixed with the
333 target type, if the build type and target type are different.
335 ** AC_REQUIRE_AUX_FILE
336 New trace macro that declares expected auxiliary files.
339 New macro that tests for a grep program that accepts as a long a line
342 ** AC_PROG_EGREP, AC_PROG_FGREP
343 These macros now require AC_PROG_GREP, and try EGREP="$GREP -E" and
344 FGREP="$GREP -F" respectively if possible, or else run a path search for
345 a program that accepts as long a line as possible.
348 New macro that tests for a sed program that truncates as few characters
351 * Major changes in Autoconf 2.59
353 Released 2003-11-04, by Akim Demaille
355 ** ac_abs_builddir etc.
356 Absolute file names were actually relative in 2.58.
358 * Major changes in Autoconf 2.58
360 Released 2003-11-04, by Akim Demaille
363 core.* files are no longer removed, as they may be valid user files.
365 ** autoreconf and auxiliary directory
366 Autoreconf creates the auxiliary directory if needed. This is
367 especially useful for initial "bootstrapping" of fresh CVS checkouts.
369 ** AC_CONFIG_MACRO_DIR
370 Use this macro to declare the directory for local M4 macros for aclocal.
373 No longer includes twice the same file in LIBOBJS if invoked
376 ** AC_CONFIG_COMMANDS
377 The directory for its first argument is automatically created. For
380 AC_CONFIG_COMMANDS([src/modules.hh], [...])
382 $top_builddir/src/ is created if needed.
384 ** Autotest and local.at
385 The optional file local.at is always included in Autotest test suites.
388 The warnings are always issued, including with cached runs.
389 This became a significant problem since aclocal and automake can
390 run autoconf behind the scene.
392 ** autoheader warnings
393 The warnings of autoheader can be turned off, using --warning.
394 For instance, -Wno-obsolete disables the complaints about acconfig.h
395 and other deprecated constructs.
398 AC_C_RESTRICT, AC_INCLUDES_DEFAULT, AC_LANG_ASSERT, AC_LANG_WERROR,
401 ** AC_DECL_SYS_SIGLIST
405 Now checks that mktime is the inverse of localtime.
407 ** Improve DJGPP portability
408 The Autoconf tools and configure behave better under DJGPP.
410 ** Present But Cannot Be Compiled
411 New FAQ section dedicated to the mystic
413 configure: WARNING: pi.h: present but cannot be compiled
414 configure: WARNING: pi.h: check for missing prerequisite headers?
415 configure: WARNING: pi.h: proceeding with the preprocessor's result
418 ** Concurrent executions of autom4te
419 autom4te now locks its internal files, which enables concurrent
420 executions of autom4te, likely to happen if automake, autoconf,
421 autoheader etc. are run simultaneously.
424 Use of Libtool 1.5 and higher is encouraged. Compatibility with
425 Libtool pre-1.4 is not checked.
428 Testsuites no longer rerun failed tests in verbose mode; instead,
429 failures are logged while the test is run.
431 In addition, expected failures can be marked as such.
433 * Major changes in Autoconf 2.57
435 Released 2002-12-03 by Paul Eggert.
437 Bug fixes for problems with AIX linker, with freestanding C compilers,
438 with GNU M4 limitations, and with obsolete copies of GNU documents.
440 The Free Documentation License has been upgraded from 1.1 to 1.2.
442 * Major changes in Autoconf 2.56
444 Released 2002-11-15 by Akim Demaille.
446 One packaging problem fixed (config/install-sh was not executable).
448 * Major changes in Autoconf 2.55
450 Released 2002-11-14 by Akim Demaille.
454 Have your configure.ac checked by autoscan ("autoscan").
455 Try the warning options ("autoreconf -fv -Wall").
459 - AC_CHECK_HEADER, AC_CHECK_HEADERS
460 More information on proper use.
462 - Writing Test Programs
464 This sections explains how to write good test sources to use with
465 AC_COMPILE_IFELSE etc. It documents AC_LANG_PROGRAM and so forth.
467 - AC_FOO_IFELSE vs. AC_TRY_FOO
469 Explains why Autoconf moves from AC_TRY_COMPILE etc. to
470 AC_COMPILE_IFELSE and AC_LANG_PROGRAM etc.
474 - Is more robust to different Gettext installations.
476 - Produces messages (when --verbose) to be understood by Emacs'
479 - Supports -W/--warnings.
482 Once the GNU Build System reinstalled, run `./config.status
483 --recheck && ./config.status && make' if possible.
487 - Supports --cache, and --no-cache.
489 - ~/.autom4te.cfg makes it possible to disable the caching mechanism
490 (autom4te.cache). See `Customizing autom4te' in the documentation.
497 Support for the obsoleted options -m, --macrodir, -l, --localdir is
498 dropped in favor of the safer --include/--prepend-include scheme.
503 AC_COMPILER_IFELSE, AC_FUNC_MBRTOWC, AC_HEADER_STDBOOL,
504 AC_LANG_CONFTEST, AC_LANG_SOURCE, AC_LANG_PROGRAM, AC_LANG_CALL,
505 AC_LANG_FUNC_TRY_LINK, AC_MSG_FAILURE, AC_PREPROC_IFELSE.
508 Obsoleted macros are kept for Autoconf backward compatibility, but
509 should be avoided in configure.ac. Running autoupdate is advised.
512 - AC_DEFINE/AC_DEFINE_UNQUOTED
514 We have to stop using the old compatibility scheme --that tried to
515 avoid useless backslashes-- because Libtool 1.4.3 contains a
517 AC_DEFINE([error_t], [int],
518 [Define to a type to use for \`error_t' if it is not
519 otherwise available.])
521 We have to quote the single quotes and backslashes with \. The old
522 compatibility scheme saw that ` was backslashed, and therefore did
523 not quote the single quote... Failure. Hence, Autoconf 2.54 is not
524 compatible with Libtool. Autoconf 2.55 is, but in some cases might
525 produce more \ than wanted.
527 Please, note that in the future the same problem will happen with
528 AC_MSG_*: use `autoreconf -f -Wall'.
532 - Portability of the Autoconf package to Solaris.
534 - Spurious warnings caused by config.status.
535 This bug is benign, but painful: on some systems (typically
536 FreeBSD), warnings such as:
538 config.status: creating Makefile
539 mv: Makefile: set owner/group (was: 1357/0): Operation not permitted
541 could be issued. This is fixed.
544 Simultaneous executions of config.status are possible again.
546 - Precious variables accumulation
548 config.status could stack several copies of the precious variables
552 ** Plans for later versions
556 The compatibility hooks with the old scheme will be completely
557 removed. Please, advice/use `--build', `--host', and `--target'
560 - AC_CHECK_HEADER, AC_CHECK_HEADERS
562 The tests will be stricter, please make sure your invocations are
567 Shell functions will gradually be introduced, probably starting with
568 Autotest. If you know machines which are in use that you suspect
569 *not* to support shell functions, please run the test suite of
570 Autoconf 2.55 on it, and report the results to
571 bug-autoconf@gnu.org.
575 Special characters in AC_MSG_* need not be quoted. Currently,
576 Autoconf has heuristics to decide when a string is escaped, or has
577 to be escaped. This scheme is fragile, and will be removed; the
578 only risk is uglified messages. Please, run `autoreconf -f -Wall'
579 to find occurrences that will be affected.
581 * Major changes in Autoconf 2.54
583 Released 2002-09-13 by Akim Demaille.
587 - autoreconf no longer changes the version of the gettext/po/intl
588 support files. It now adds the files the correspond to the
589 AM_GNU_GETTEXT_VERSION declared in configure.ac.
591 Warning: It now relies on the 'autopoint' program, which is part
592 of GNU gettext 0.11.4 and newer.
594 Please note that you need to have a GNU gettext version that
595 corresponds at least to the AM_GNU_GETTEXT_VERSION declared
596 in configure.ac. You can upgrade to newer GNU gettext versions,
597 though, without needing to change configure.ac.
599 - The -I DIR or --include=DIR option now appends DIR to the include path
600 instead of prepending; this is for consistency with other GNU tools.
601 The new -B DIR or --prepend-include=DIR option has the old behavior.
606 Now handles all the gory details about LIBOBJS and LTLIBOBJS.
607 Please, remove lines such as
609 # This is necessary so that .o files in LIBOBJS are also
610 # built via the ANSI2KNR-filtering rules.
611 LIBOBJS=`echo $LIBOBJS|sed 's/\.o /\$U.o /g;s/\.o$/\$U.o/'`
613 and read the `AC_LIBOBJ vs LIBOBJS' section. Do not define U in
614 your Makefiles either.
616 - AC_CONFIG_LINKS now makes copies if it can't make links.
618 - AC_FUNC_FNMATCH now tests only for POSIX compatibility, reverting to
619 Autoconf 2.13 behavior. The new macro AC_FUNC_FNMATCH_GNU also
620 tests for GNU extensions to fnmatch, and replaces fnmatch if needed.
622 - AC_FUNC_SETVBUF_REVERSED no longer fails when cross-compiling.
624 - AC_PROG_CC_STDC is integrated into AC_PROG_CC.
626 - AC_PROG_F77 default search no longer includes cf77 and cfg77.
630 AC_C_BACKSLASH_A, AC_CONFIG_LIBOBJ_DIR, AC_GNU_SOURCE,
631 AC_PROG_EGREP, AC_PROG_FGREP, AC_REPLACE_FNMATCH,
632 AC_FUNC_FNMATCH_GNU, AC_FUNC_REALLOC, AC_TYPE_MBSTATE_T.
635 looks for getloadavg.c in the CONFIG_LIBOBJ_DIR.
638 Now defines HAVE_MALLOC to 0 if `malloc' does not work, and asks
639 for an AC_LIBOBJ replacement.
643 - Spurious complaints from `m4_bmatch' about invalid regular
644 expressions are suppressed.
646 - Empty top_builddirs are properly handled.
648 - AC_CHECK_MEMBER works correctly when the member is an aggregate.
651 Now colon in the optional path arguments are properly handled.
653 ** Improved portability
655 - Both Autoconf the package, and the scripts it produces, should run
656 more reliably with Zsh. Bear in mind it is the default Bourne shell
659 - Autoconf and the scripts it produces no longer assume the existence of
660 the obsolescent commands egrep and fgrep.
664 - Limitations of Make
668 The GNATS base moved to
669 http://bugs.gnu.org/cgi-bin/gnatsweb.pl?database=autoconf
670 (It is no longer available, though.)
675 Now contains the list of ouput variables and files (AC_SUBST,
678 * Major changes in Autoconf 2.53
680 Released 2002-03-08 by Akim Demaille.
684 Perl 5.005_03 or later is required: autom4te is written in Perl and is
685 needed by autoconf. autoheader, autoreconf, ifnames, and autoscan are
691 Argument requirements, output variables, defined macros.
692 - M4sugar, M4sh, Autotest
694 - Double quoting macros
695 AC_TRY_CPP, AC_TRY_COMPILE, AC_TRY_LINK and AC_TRY_RUN.
697 The Autoconf manual is now distributed under the terms of the GNU FDL.
698 - Section `Hosts and Cross-Compilation'
699 Explains the rationale for the 2.5x changes in the cross-compilation
700 chain, and in the relationships between build, host, and target
702 Emphasizes that `cross-compilation' == `--host is given'.
703 If you are working on compilers etc., be sure to read this section.
704 - Section `AC_LIBOBJ vs. LIBOBJS'
705 Explains why assigning LIBOBJS directly is now an error.
706 Details how to update the code.
711 Now used instead of hard coded line numbers.
712 This eases the comparison of `configure's, and diminishes the
713 pressure over control version archives.
714 Automatic replacement for shells that don't support this feature.
715 - New output variables
716 @builddir@, @top_builddir@, @abs_srcdir@, @abs_top_srcdir@, @abs_builddir@,
721 Autoconf and Autotest modes are provided.
726 New, used by the Autoconf suite to cache and speed up most processing.
728 Supported by autom4te, autoconf and autoheader.
730 Replaces --autoconf-dir and --localdir in autoconf, autoheader,
731 autoupdate, and autoreconf.
733 No longer passes --cygnus, --foreign, --gnits, --gnu, --include-deps:
734 automake options are to be given via AUTOMAKE_OPTIONS.
736 Runs gettextize and libtoolize when appropriate.
738 --m4dir is no longer supported.
740 Now runs only in the specified directories, defaulting to `.',
741 but understands AC_CONFIG_SUBDIRS for dependent directories.
742 Before, it used to run on all the `configure.ac' found in the
744 Independent packages are properly updated.
748 - The top level $prefix is propagated to the AC_CONFIG_SUBDIRS configures.
750 Under the user pressure, $? is finally available. Probably a mistake.
751 - AC_F77_LIBRARY_LDFLAGS now supports the HP/UX f90 compiler.
752 - Precious variables accumulation
753 config.status could stack several copies of the precious variables
755 - AC_PATH_PROG and family.
756 Works properly when given a literal path.
758 Somewhere since 2.13, the result had been reversed.
762 - AC_C_BIGENDIAN supports the cross-compiling case.
763 - AC_C_BIGENDIAN accepts ACTION-IF-TRUE, ACTION-IF-FALSE, and
764 ACTION-IF-UNKNOWN arguments. All are facultative, and the default
765 for ACTION-IF-TRUE is to define WORDS_BIGENDIAN like AC_C_BIGENDIAN
767 - AC_C_LONG_DOUBLE now succeeds only if `long double' has more range or
768 precision than `double'.
773 It now defines the preprocessor symbols PACKAGE_NAME,
774 PACKAGE_TARNAME, PACKAGE_VERSION, PACKAGE_STRING, and
778 Admits a fourth optional parameter: the tar name.
780 - AC_CONFIG_COMMANDS, HEADERS, FILES, LINKS.
781 Provide the user with srcdir, ac_srcdir, ac_top_srcdir, ac_builddir,
782 ac_top_builddir, ac_abs_srcdir, ac_abs_top_srcdir, ac_abs_builddir,
785 - AC_CONFIG_COMMANDS, HEADERS, FILES, LINKS and AC_OUTPUT.
786 Are much less expensive when using long lists of files.
789 Works with shell variables, and non alphanumeric names.
793 - AC_FUNC_STRERROR_R now sets STRERROR_R_CHAR_P, not HAVE_WORKING_STRERROR_R,
794 because POSIX 1003.1-200x draft 7 says strerror_r returns int, not char *.
796 - AC_FUNC_STRTOD substitutes POW_LIB.
801 * Major changes in Autoconf 2.52
803 Released 2001-07-18 by Akim Demaille.
808 This feature was present in autoconf 2.50 but was not documented.
809 For example, `@<:@' is translated to `[' just before output. This
810 is useful when writing strings that contain unbalanced quotes, or
811 other hard-to-quote constructs.
812 - m4_pattern_forbid, m4_pattern_allow
813 - Tips for upgrading from 2.13.
814 - Using autoscan to maintain a configure.ac.
817 - Now include stdint.h.
818 - sys/types.h and sys/stat.h are guarded.
819 - strings.h is included if available, and not conflicting with string.h.
822 - The test suite is more robust and presents less false failures.
823 - Invocation of GNU M4 now robust to POSIXLY_CORRECT.
824 - configure accepts --prefix='' again.
825 - AC_CHECK_LIB works properly when its first argument is not a
827 - HAVE_INTTYPES_H is defined only if not conflicting with sys/types.h.
828 - build_, host_, and target_alias are AC_SUBST as in 2.13.
829 - AC_ARG_VAR properly propagates precious variables inherited from the
830 environment to ./config.status.
831 - Using --program-suffix/--program-prefix is portable.
832 - Failures to detect the default compiler's output extension are less
834 - `config.status foo' works properly when `foo' depends on variables
835 set in an AC_CONFIG_THING INIT-CMD.
836 - autoheader is more robust to broken input.
837 - Fixed Fortran name-mangling and link tests on a number of systems,
838 e.g. NetBSD; see AC_F77_DUMMY_MAIN, below.
841 - AC_CHECK_HEADER and AC_CHECK_HEADERS support a fourth argument to
842 specify pre-includes. In this case, the headers are compiled with
843 cc, not merely preprocessed by cpp. Therefore it is the _usability_
844 of a header which is checked for, not just its availability.
845 - AC_ARG_VAR refuses to run configure when precious variables have
847 - Versions of compilers are dumped in the logs.
848 - AC_CHECK_TYPE recognizes use of `foo_t' as a replacement type.
851 - AC_PATH_XTRA only adds -ldnet to $LIBS if it's needed to link.
852 - AC_FUNC_WAIT3 and AC_SYS_RESTARTABLE_SYSCALLS are obsoleted.
853 - AM_FUNC_ERROR_AT_LINE, AM_FUNC_FNMATCH, AM_FUNC_MKTIME,
854 AM_FUNC_OBSTACK, and AM_FUNC_STRTOD are now activated.
855 Be sure to read `Upgrading from Version 2.13' to understand why
856 running `autoupdate' is needed.
857 - AC_F77_DUMMY_MAIN, AC_F77_MAIN: new macros to detect whether
858 a main-like routine is required/possible when linking C/C++ with
859 Fortran. Users of e.g. AC_F77_WRAPPERS should be aware of these.
860 - AC_FUNC_GETPGRG behaves better when cross-compiling.
862 * Major changes in Autoconf 2.51
863 There was no release of Autoconf 2.51 since some packagers had used
864 this version number without permission to ship intermediary versions
865 of 2.50. The version was skipped to avoid confusion.
867 * Major changes in Autoconf 2.50
869 Released 2001-05-21 by Akim Demaille.
872 There have been far too many to enumerate them here. Check out
873 ChangeLog if you really want to know more.
875 ** Improved documentation
876 In particular, portability issues are better covered.
879 All the standard GNU Makefile targets are supported. The layout has
880 changed: m4/ holds the M4 extensions Autoconf needs for its
881 configuration, doc/ contains the documentation, and tests/ contains
884 ** Man pages are provided
885 For autoconf, autoreconf, autoupdate, autoheader, autoscan, ifnames,
886 config.guess, config.sub.
890 Provides a safe and powerful means to trace the macro uses. This
891 provide the parsing layer for tools which need to `study'
895 Specify what category of warnings should be enabled.
897 - When recursing into subdirectories, try for configure.gnu before
898 configure to adapt for packages not using autoconf on case-insensitive
902 More errors are now caught (circular AC_REQUIRE dependencies,
903 AC_DEFINE in the action part of an AC_CACHE_CHECK, too many pops
904 etc.). In addition, their location and call stack are given.
907 autoupdate is much more powerful, and is able to provide the glue code
908 which might be needed to move from an old macro to its newer
911 You are strongly encouraged to use it to modernize both your
912 `configure.in' and your .m4 extension files.
915 The internal machinery of autoheader has completely changed. As a
916 result, using `acconfig.h' should be considered to be obsoleted, and
917 you are encouraged to get rid of it using the AH macros.
922 ** Fortran 77 compilers
923 Globally, the support for Fortran 77 is considerably improved.
925 Support for automatically determining a Fortran 77 compiler's
926 name-mangling scheme. New CPP macros F77_FUNC and F77_FUNC_ are
927 provided to wrap C/C++ identifiers, thus making it easier and more
928 transparent for C/C++ to call Fortran 77 routines, and Fortran 77 to
929 call C/C++ routines. See the Texinfo documentation for details.
932 The test suite no longer uses DejaGNU. It should be easy to submit
933 test cases in this new framework.
936 - --help, --help=long, -hl
937 no longer dumps useless items.
939 lists only specific options.
940 - --help=recursive, -hr
941 displays the help of all the embedded packages.
942 - Remembers environment variables when reconfiguring.
943 The previous scheme to set envvar before running configure was
945 what prevented configure from remembering the environment in which
946 it was run, therefore --recheck was run in an inconsistent
947 environment. Now, one should run
949 and then --recheck will work properly. Variables declared with
950 AC_ARG_VAR are also preserved.
952 $build defaults to `config.guess`, $host to $build, and then $target
954 Cross-compilation is a global status of the package, it no longer
955 depends upon the current language.
956 Cross compilation is enabled iff the user specified `--host'.
957 `configure' now fails if it can't run the executables it compiles,
958 unless cross-compilation is enabled.
960 The cache file is disabled by default. The new options
961 `--config-cache', `-C' set the cache to `config.cache'.
965 Much faster on most architectures.
966 - concurrent executions
967 It is safe to use `make -j' with config.status.
968 - human interface improved
969 It is possible to invoke
970 ./config.status foobar
971 instead of the former form (still valid)
972 CONFIG_COMMANDS= CONFIG_HEADERS= CONFIG_LINKS= \
973 CONFIG_FILES=foobar:foo.in:bar.in \
975 The same holds for configuration headers and links.
976 You can instantiate unknown files and headers:
977 ./config.status --header foo.h:foo.h.in --file bar:baz
978 - has a useful --help
979 - accepts special file name "-" for stdin/stdout
984 Specify additional copyright information.
987 Now expects the identity of the package as argument.
991 Most macros, if not all, now strictly follow the `one quotation
992 level' rule. This results in a more predictable expansion.
995 A sly bug in the AC_REQUIRE machinery, which could produce incorrect
996 configure scripts, was fixed by Axel Thimm.
1000 Document and ask for the registration of an envvar.
1003 Specifies the file which `configure' should look for when trying to
1004 find the source tree (used to be handled by AC_INIT).
1006 - AC_CONFIG_COMMANDS
1007 To add new actions to config.status. Should be used instead of
1011 Replaces AC_LINK_FILES.
1013 - AC_CONFIG_HEADERS, AC_CONFIG_COMMANDS, AC_CONFIG_SUBDIRS,
1014 AC_CONFIG_LINKS, and AC_CONFIG_FILES
1015 They now obey sh: you should no longer use shell variables as
1016 argument. Instead of
1018 test "$package_foo_enabled" = yes && $my_subdirs="$my_subdirs foo"
1019 AC_CONFIG_SUBDIRS($my_subdirs)
1023 if test "$package_foo_enabled" = yes; then
1024 AC_CONFIG_SUBDIRS(foo)
1028 To format an Autoconf macro's help string so that it looks pretty
1029 when the user executes `configure --help'.
1032 ** Generic Test Macros
1034 The interface of the AC_CHECK families of macros (decl, header,
1035 type, member, func) is now uniform. They support the same set of
1038 - AC_CHECK_DECL, AC_CHECK_DECLS
1039 To check whether a symbol is declared.
1041 - AC_CHECK_SIZEOF, AC_C_CHAR_UNSIGNED.
1042 No longer need a cross-compilation default.
1045 The test it performs is much more robust than previously, and makes
1046 it possible to test builtin types in addition to typedefs.
1047 It is now schizophrenic:
1048 - AC_CHECK_TYPE(TYPE, REPLACEMENT)
1049 remains for backward compatibility, but its use is discouraged.
1050 - AC_CHECK_TYPE(TYPE, IF-FOUND, IF-NOT-FOUND, INCLUDES)
1051 behaves exactly like the other AC_CHECK macros.
1054 Checks whether given types are supported by the system.
1056 - AC_CHECK_MEMBER, AC_CHECK_MEMBERS
1057 Check for given members in aggregates (e.g., pw_gecos in struct
1061 Checks if the compiler supports ISO C, included when needs special
1065 Checking whether the preprocessor indicates missing includes by the
1066 error code. stderr is checked by AC_TRY_CPP only as a fallback.
1069 Takes a language as argument and replaces AC_LANG_C,
1070 AC_LANG_CPLUSPLUS and AC_LANG_FORTRAN77.
1072 - AC_LANG_PUSH, AC_LANG_POP
1073 Are preferred to AC_LANG_SAVE, AC_LANG_RESTORE.
1076 - AC_FUNC_CHOWN, AC_FUNC_MALLOC, AC_FUNC_STRERROR_R,
1077 AC_FUNC_LSTAT_FOLLOWS_SLASHED_SYMLINK, AC_FUNC_STAT, AC_FUNC_LSTAT,
1078 AC_FUNC_ERROR_AT_LINE, AC_FUNC_OBSTACK, AC_FUNC_STRTOD, AC_FUNC_FSEEKO.
1082 Sets GETGROUPS_LIBS.
1084 - AC_FUNC_GETLOADAVG
1085 Defines `HAVE_STRUCT_NLIST_N_UN_N_NAME' instead of `NLIST_NAME_UNION'.
1088 Now integrates `AC_DECL_YYTEXT' which is obsoleted.
1091 Arrange for large-file support.
1093 - AC_EXEEXT, AC_OBJEXT
1094 You are no longer expected to use them: their computation is
1095 performed by default.
1097 ** C++ compatibility
1098 Every macro has been revisited in order to support at best CC=c++.
1100 Major changes in Autoconf 2.14:
1101 There was no release of GNU Autoconf 2.14.
1103 Major changes in Autoconf 2.13:
1105 Released 1999-05-01 by Ben Elliston.
1107 * Support for building on Win32 systems where the only available C or
1108 C++ compiler is the Microsoft Visual C++ command line compiler
1109 (`cl'). Additional support for building on Win32 systems which are
1110 using the Cygwin or Mingw32 environments.
1111 * Support for alternative object file and executable file extensions.
1112 On Win32, for example, these are .obj and .exe. These are discovered
1113 using AC_OBJEXT and AC_EXEEXT, which substitute @OBJEXT@ and
1114 @EXEEXT@ in the output, respectively.
1115 * New macros: AC_CACHE_LOAD, AC_CACHE_SAVE, AC_FUNC_SELECT_ARGTYPES,
1116 AC_VALIDATE_CACHED_SYSTEM_TUPLE, AC_SEARCH_LIBS, AC_TRY_LINK_FUNC,
1117 AC_C_STRINGIZE, AC_CHECK_FILE(S), AC_PROG_F77 (and friends).
1118 * AC_DEFINE now has an optional third argument for a description to be
1119 placed in the config header input file (e.g. config.h.in).
1120 * The C++ code fragment compiled for the C++ compiler test had to be
1121 improved to include an explicit return type for main(). This was
1122 causing failures on systems using recent versions of the EGCS C++
1124 * Fixed an important bug in AC_CHECK_TYPE that would cause a configure
1125 script to report that `sometype_t' was present when only `type_t'
1127 * Merge of the FSF version of config.guess and config.sub to modernize
1128 these scripts. Add support for a few new hosts in config.guess.
1129 Incorporate latest versions of install-sh, mkinstalldirs and
1130 texinfo.tex from the FSF.
1131 * autoreconf is capable of running automake if necessary (and
1133 * Support for Fortran 77. See the Texinfo documentation for details.
1134 * Bug fixes and workarounds for quirky bugs in vendor utilities.
1136 Major changes in Autoconf 2.12:
1138 Released 1996-11-26 by David J. MacKenzie
1140 * AC_OUTPUT and AC_CONFIG_HEADER can create output files by
1141 concatenating multiple input files separated by colons, like so:
1142 AC_CONFIG_HEADER(config.h:conf.pre:config.h.in:conf.post)
1143 AC_OUTPUT(Makefile:Makefile.in:Makefile.rules)
1144 The arguments may be shell variables, to compute the lists on the fly.
1145 * AC_LINK_FILES and AC_CONFIG_SUBDIRS may be called multiple times.
1146 * New macro AC_OUTPUT_COMMANDS adds more commands to run in config.status.
1149 Major changes in Autoconf 2.11:
1151 Released November 18th, 1996, by David J. MacKenzie
1153 * AC_PROG_CC and AC_PROG_CXX check whether the compiler works.
1154 They also default CFLAGS/CXXFLAGS to "-g -O2" for gcc, instead of "-g -O".
1155 * AC_REPLACE_FUNCS defines HAVE_foo if the system has the function `foo'.
1156 * AC_CONFIG_HEADER expands shell variables in its argument.
1157 * New macros: AC_FUNC_FNMATCH, AC_FUNC_SETPGRP.
1158 * The "checking..." messages and the source code for test programs that
1159 fail are saved in config.log.
1160 * Another workaround has been added for seds with small command length limits.
1161 * config.sub and config.guess recognize more system types.
1164 Major changes in Autoconf 2.10:
1166 Released May 7th, 1996, by Roland McGrath
1169 * The cache variable names used by `AC_CHECK_LIB(LIB, FUNC, ...)' has
1170 changed: now $ac_cv_lib_LIB_FUNC, previously $ac_cv_lib_LIB.
1172 Major changes in Autoconf 2.9:
1174 Released March 16th, 1996, by Roland McGrath
1178 Major changes in Autoconf 2.8:
1180 Released March 8th, 1996, by Roland McGrath
1184 Major changes in Autoconf 2.7:
1186 Released November 22nd, 1995, by David J. MacKenzie
1190 Major changes in Autoconf 2.6:
1192 Released November 20th, 1995, by David J. MacKenzie
1196 Major changes in Autoconf 2.5:
1198 Released November 17th, 1995, by Roland McGrath
1200 * New configure options --bindir, --libdir, --datadir, etc., with
1201 corresponding output variables.
1202 * New macro: AC_CACHE_CHECK, to make using the cache easier.
1203 * config.log contains the command being run as well as any output from it.
1204 * AC_CHECK_LIB can check for libraries with "." or "/" or "+" in their name.
1205 * AC_PROG_INSTALL doesn't cache a name for install-sh, for sharing caches.
1206 * AC_CHECK_PROG, AC_PATH_PROG, AC_CHECK_PROGS, AC_PATH_PROGS, and
1207 AC_CHECK_TOOL can search a path other than $PATH.
1208 * AC_CHECK_SIZEOF takes an optional size to use when cross-compiling.
1210 Major changes in Autoconf 2.4:
1212 Released June 14th, 1995, by David J. MacKenzie
1214 * Fix a few bugs found by Emacs testers.
1216 Major changes in Autoconf 2.3:
1218 Released March 27th, 1995, by David J. MacKenzie
1220 * Fix the cleanup trap in several ways.
1221 * Handle C compilers that are picky about option placement.
1222 * ifnames gets the version number from the right directory.
1224 Major changes in Autoconf 2.2:
1226 Released March 8th, 1995, by David J. MacKenzie
1228 * The ifnames utility is much faster but requires a "new awk" interpreter.
1229 * AC_CHECK_LIB and AC_HAVE_LIBRARY check and add the new
1230 library before existing libs, not after, in case it uses them.
1231 * New macros: AC_FUNC_GETPGRP, AC_CHECK_TOOL.
1232 * Lots of bug fixes.
1233 * Many additions to the TODO file :-)
1235 Major changes in Autoconf 2.1:
1237 Released November 4th, 1994, by David J. MacKenzie
1240 * More explanations in the manual.
1241 * Fix a spurious failure in the testsuite.
1242 * Clarify some warning messages.
1243 * autoreconf by default only rebuilds configure and config.h.in files
1244 that are older than any of their particular input files; there is a
1245 --force option to use after installing a new version of Autoconf.
1247 Thanks to everybody who's submitted changes and additions to Autoconf!
1248 I've incorporated many of them, and am still considering others for
1249 future releases -- but I didn't want to postpone this release indefinitely.
1251 Caution: don't indiscriminately rebuild configure scripts with
1252 Autoconf version 2. Some configure.in files need minor adjustments to
1253 work with it; the documentation has a chapter on upgrading. A few
1254 configure.in files, including those for GNU Emacs and the GNU C
1255 Library, need major changes because they relied on undocumented
1256 internals of version 1. Future releases of those packages will have
1257 updated configure.in files.
1259 It's best to use GNU M4 1.3 (or later) with Autoconf version 2.
1260 Autoconf now makes heavy use of M4 diversions, which were implemented
1261 inefficiently in GNU M4 releases before 1.3.
1263 Major changes in Autoconf 2.0:
1265 Released October 26th, 1994, by David J. MacKenzie
1267 ** New copyright terms:
1268 * There are no restrictions on distribution or use of configure scripts.
1271 * Autoconf manual is reorganized to make information easier to find
1272 and has several new indexes.
1273 * INSTALL is reorganized and clearer and is now made from Texinfo source.
1276 * autoscan to generate a preliminary configure.in for a package by
1277 scanning its source code for commonly used nonportable functions,
1278 programs, and header files.
1279 * ifnames to list the symbols used in #if and #ifdef directives in a
1281 * autoupdate to update a configure.in to use the version 2 macro names.
1282 * autoreconf to recursively remake configure and configuration header
1283 files in a source tree.
1285 ** Changed utilities:
1286 * autoheader can take pieces of acconfig.h to replace config.h.{top,bot}.
1287 * autoconf and autoheader can look for package-local definition files
1288 in an alternate directory.
1291 * AC_CACHE_VAL to share results of tests between configure runs.
1292 * AC_DEFUN to define macros, automatically AC_PROVIDE them, and ensure
1293 that macros invoked with AC_REQUIRE don't interrupt other macros.
1294 * AC_CONFIG_AUX_DIR, AC_CANONICAL_SYSTEM, AC_CANONICAL_HOST, AC_LINK_FILES to
1295 support deciding unguessable features based on the host and target types.
1296 * AC_CONFIG_SUBDIRS to recursively configure a source tree.
1297 * AC_ARG_PROGRAM to use the options --program-prefix,
1298 --program-suffix, and --program-transform-name to change the names
1299 of programs being installed.
1300 * AC_PREFIX_DEFAULT to change the default installation prefix.
1301 * AC_TRY_COMPILE to compile a test program without linking it.
1302 * AC_CHECK_TYPE to check whether sys/types.h or stdlib.h defines a given type.
1303 * AC_CHECK_LIB to check for a particular function and library.
1304 * AC_MSG_CHECKING and AC_MSG_RESULT to print test results, on a single line,
1305 whether or not the test succeeds. They obsolete AC_CHECKING and AC_VERBOSE.
1306 * AC_SUBST_FILE to insert one file into another.
1307 * AC_FUNC_MEMCMP to check whether memcmp is 8-bit clean.
1308 * AC_FUNC_STRFTIME to find strftime even if it's in -lintl.
1309 * AC_FUNC_GETMNTENT to find getmntent even if it's in -lsun or -lseq.
1310 * AC_HEADER_SYS_WAIT to check whether sys/wait.h is POSIX.1 compatible.
1313 * Many macros renamed systematically, but old names are accepted for
1314 backward compatibility.
1315 * AC_OUTPUT adds the "automatically generated" comment to
1316 non-Makefiles where it finds @configure_input@ in an input file, to
1317 support files with various comment syntaxes.
1318 * AC_OUTPUT does not replace "prefix" and "exec_prefix" in generated
1319 files when they are not enclosed in @ signs.
1320 * AC_OUTPUT allows the optional environment variable CONFIG_STATUS to
1321 override the file name "config.status".
1322 * AC_OUTPUT takes an optional argument for passing variables from
1323 configure to config.status.
1324 * AC_OUTPUT and AC_CONFIG_HEADER allow you to override the input-file names.
1325 * AC_OUTPUT automatically substitutes the values of CFLAGS, CXXFLAGS,
1326 CPPFLAGS, and LDFLAGS from the environment.
1327 * AC_PROG_CC and AC_PROG_CXX now set CFLAGS and CXXFLAGS, respectively.
1328 * AC_PROG_INSTALL looks for install-sh or install.sh in the directory
1329 specified by AC_CONFIG_AUXDIR, or srcdir or srcdir/.. or
1330 srcdir/../.. by default.
1331 * AC_DEFINE, AC_DEFINE_UNQUOTED, and AC_SUBST are more robust and smaller.
1332 * AC_DEFINE no longer prints anything, because of the new result reporting
1333 mechanism (AC_MSG_CHECKING and AC_MSG_RESULT).
1334 * AC_VERBOSE pays attention to --quiet/--silent, not --verbose.
1335 * AC_ARG_ENABLE and AC_ARG_WITH support whitespace in the arguments to
1336 --enable- and --with- options.
1337 * AC_CHECK_FUNCS and AC_CHECK_HEADERS take optional shell commands to
1338 execute on success or failure.
1339 * Checking for C functions in C++ works.
1342 * AC_REMOTE_TAPE and AC_RSH removed; too specific to tar and cpio, and
1343 better maintained with them.
1344 * AC_ARG_ARRAY removed because no one was likely using it.
1345 * AC_HAVE_POUNDBANG replaced with AC_SYS_INTERPRETER, which doesn't
1346 take arguments, for consistency with all of the other specific checks.
1349 * Comes with config.sub and config.guess, and uses them optionally.
1350 * Uses config.cache to cache test results. An alternate cache file
1351 can be selected with the --cache-file=FILE option.
1352 * Uses optional shell scripts $prefix/share/config.site and
1353 $prefix/etc/config.site to perform site or system specific initializations.
1354 * configure saves compiler output to ./config.log for debugging.
1355 * New files autoconf.m4 and autoheader.m4 load the other Autoconf macros.
1356 * acsite.m4 is the new name for the system-wide aclocal.m4.
1357 * Has a DejaGnu test suite.
1359 Major changes in Autoconf 1.11:
1361 * AC_PROG_INSTALL calls install.sh with the -c option.
1362 * AC_SET_MAKE cleans up after itself.
1363 * AC_OUTPUT sets prefix and exec_prefix if they weren't set already.
1364 * AC_OUTPUT prevents shells from looking in PATH for config.status.
1366 Plus a few other bug fixes.
1368 Major changes in Autoconf 1.10:
1370 * autoheader uses config.h.bot if present, analogous to config.h.top.
1371 * AC_PROG_INSTALL looks for install.sh in srcdir or srcdir/.. and
1373 * AC_PROG_CXX looks for cxx as a C++ compiler.
1375 Plus several bugs fixed.
1377 Major changes in Autoconf 1.9:
1379 * AC_YYTEXT_POINTER replaces AC_DECLARE_YYTEXT.
1380 * AC_SIZEOF_TYPE generates the cpp symbol name automatically,
1381 and autoheader generates entries for those names automatically.
1382 * AC_FIND_X gets the result from xmkmf correctly.
1383 * AC_FIND_X assumes no X if --without-x was given.
1384 * AC_FIND_XTRA adds libraries to the variable X_EXTRA_LIBS.
1385 * AC_PROG_INSTALL finds OSF/1 installbsd.
1387 Major changes in Autoconf 1.8:
1390 * New macros AC_LANG_C, AC_LANG_CPLUSPLUS, AC_LANG_SAVE, AC_LANG_RESTORE,
1391 AC_PROG_CXX, AC_PROG_CXXCPP, AC_REQUIRE_CPP
1392 for checking both C++ and C features in one configure script.
1393 * New macros AC_CHECKING, AC_VERBOSE, AC_WARN, AC_ERROR for printing messages.
1394 * New macros AC_FIND_XTRA, AC_MMAP, AC_SIZEOF_TYPE, AC_PREREQ,
1395 AC_SET_MAKE, AC_ENABLE.
1398 * AC_FIND_X looks for X in more places.
1399 * AC_PROG_INSTALL defaults to install.sh instead of cp, if it's in srcdir.
1400 install.sh is distributed with Autoconf.
1401 * AC_DECLARE_YYTEXT has been removed because it can't work, pending
1402 a rewrite of quoting in AC_DEFINE.
1403 * AC_OUTPUT adds its comments in C format when substituting in C files.
1404 * AC_COMPILE_CHECK protects its ECHO-TEXT argument with double quotes.
1406 ** New or changed command line options:
1407 * configure accepts --enable-FEATURE[=ARG] and --disable-FEATURE options.
1408 * configure accepts --without-PACKAGE, which sets withval=no.
1409 * configure accepts --x-includes=DIR and --x-libraries=DIR.
1410 * Giving --with-PACKAGE no argument sets withval=yes instead of withval=1.
1411 * configure accepts --help, --version, --silent/--quiet, --no-create options.
1412 * configure accepts and ignores most other Cygnus configure options, and
1413 warns about unknown options.
1414 * config.status accepts --help, --version options.
1416 ** File names and other changes:
1417 * Relative srcdir values are not made absolute.
1418 * The values of @prefix@ and @exec_prefix@ and @top_srcdir@ get substituted.
1419 * Autoconf library files are installed in ${datadir}/autoconf, not ${datadir}.
1420 * autoheader optionally copies config.h.top to the beginning of config.h.in.
1421 * The example Makefile dependencies for configure et al. work better.
1422 * Namespace cleanup: all shell variables used internally by Autoconf
1423 have names beginning with `ac_'.
1425 More big improvements are in process for future releases, but have not
1426 yet been (variously) finished, integrated, tested, or documented enough
1429 Major changes in Autoconf 1.7:
1431 * New macro AC_OBSOLETE.
1432 * Bugs in Makefile.in fixed.
1433 * AC_LONG_FILE_NAMES improved.
1435 Major changes in Autoconf 1.6:
1437 * New macro AC_LONG_64_BITS.
1438 * Multiple .h files can be created.
1439 * AC_FIND_X looks for X files directly if it doesn't find xmkmf.
1440 * AC_ALLOCA defines C_ALLOCA if using alloca.c.
1441 * --with-NAME can take a value, e.g., --with-targets=sun4,hp300bsd.
1442 * Unused --no-create option to configure removed.
1443 * autoheader doesn't change the timestamp of its output file if
1444 the file didn't change.
1445 * All macros that look for libraries now use AC_HAVE_LIBRARY.
1446 * config.status checks three optional environment variables to
1447 modify its behavior.
1448 * The usual bug fixes.
1450 Major changes in Autoconf 1.5:
1452 * New macros AC_FIND_X, AC_OFF_T, AC_STAT_MACROS_BROKEN, AC_REVISION.
1453 * autoconf and autoheader scripts have GNU standards conforming
1454 --version and --help options (they print their message and exit).
1457 Major changes in Autoconf 1.4:
1459 * New macros AC_HAVE_POUNDBANG, AC_TIME_WITH_SYS_TIME, AC_LONG_DOUBLE,
1460 AC_GETGROUPS_T, AC_DEFINE_UNQUOTED.
1461 * autoconf and autoheader use the M4 environment variable to determine the
1462 name of the M4 program to use.
1463 * The --macrodir option to autoconf and autoheader specifies the directory
1464 in which acspecific.m4, acgeneral.m4, etc. reside if not the default.
1465 * autoconf and autoheader can take `-' as their file names, which means to
1466 read stdin as input.
1467 * Resulting configure scripts can take a --verbose option which causes them
1468 to print the results of their tests.
1469 * AC_DEFINE quotes its second argument in such a way that spaces, magic
1470 shell characters, etc. will be preserved during various stages of
1471 expansion done by the shell. If you don't want this, use
1472 AC_DEFINE_UNQUOTED instead.
1473 * Much textual processing done with external calls to tr and sed have been
1474 internalized with builtin M4 `patsubst' and `translit' calls.
1475 * AC_OUTPUT doesn't hardwire the file names it outputs. Instead, you can
1476 set the shell variables `gen_files' and `gen_config' to the list of
1477 file names to output.
1478 * AC_DECLARE_YYTEXT does an AC_SUBST of `LEX_OUTPUT_ROOT', which may be
1479 "lex.yy" or "lexyy", depending on the system.
1480 * AC_PROGRAMS_CHECK takes an optional third arg. If given, it is used as
1482 * If AC_ALLOCA chooses alloca.c, it also defines STACK_DIRECTION.
1483 * AC_CONST works much more reliably on more systems.
1486 Major changes in Autoconf 1.3:
1488 configure no longer requires awk for packages that use a config.h.
1489 Support handling --with-PACKAGE options.
1490 New `autoheader' script to create `config.h.in' from `configure.in'.
1491 Ignore troublesome -lucb and -lPW when searching for alloca.
1492 Rename --exec_prefix to --exec-prefix for GNU standards conformance.
1493 Improve detection of STDC library.
1494 Add AC_HAVE_LIBRARY to check for non-default libraries.
1495 Function checking should work with future GNU libc releases.
1497 Major changes in Autoconf 1.2:
1499 The --srcdir option is now usually unnecessary.
1500 Add a file containing sample comments describing CPP macros.
1501 A comment in config.status tells which host it was configured on.
1502 Substituted variable values can now contain commas.
1503 Fix bugs in various feature checks.
1505 Major changes in Autoconf 1.1:
1507 Added AC_STRCOLL macro.
1508 Made AC_GETLOADAVG check for more things.
1509 AC_OUTPUT argument is now optional.
1514 Copyright (C) 1993, 1994, 1995, 1996, 1998, 1999, 2000, 2001, 2002,
1515 2003, 2004, 2005, 2006, 2007 Free Software Foundation, Inc.
1517 This file is part of GNU Autoconf.
1519 GNU Autoconf is free software; you can redistribute it and/or modify
1520 it under the terms of the GNU General Public License as published by
1521 the Free Software Foundation; either version 2, or (at your option)
1524 GNU Autoconf is distributed in the hope that it will be useful,
1525 but WITHOUT ANY WARRANTY; without even the implied warranty of
1526 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
1527 GNU General Public License for more details.
1529 You should have received a copy of the GNU General Public License
1530 along with GNU Autoconf; see the file COPYING. If not, write to
1531 the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
1532 Boston, MA 02110-1301, USA.